Electrical connector for neutral bars



Munich 17, 1964 c. w. WOLF ELECTRICAL CONNECTOR FOR NEUTRAL BARS 2Sheets-Sheet 1 Fiied June 28, 1961 INVENTQR. J a mmz Maf WM. 33 L. 8 4.

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March 17, 1964 c. w; WOLF ELECTRICAL CONNECTOR FOR NEUTRAL BARS 2Sheets-Sheet 2 Filed June 28, 1961 United States Patent Office 3,125,398Patented Mar. 17, 1964 3,125,398 ELECTRICAL CONNECTOR FOR NEUTRAL BARSCienient W. Wolf, Mount Clemens, Mich., assignor to Square D Company,Park Ridge, Ill., a corporation of Michigan Filed June 28, 1961, Ser.No. 122,376 6 Claims. (Cl. 339-272) This invention relates generally toneutral bars such as are commonly employed with electrical panelboardsor load centers, and more particularly to a connector which is readilyattachable to such neutral bars for receiving a larger wire than can beaccommodated by the neutral bar itself. The principal use of theconnector of this invention is in existing panelboards having circuitbreakers therein of a predetermined maximum current rating and havingneutral bars therein constructed to accommodate associated neutral wiresof a predetermined maximum diameter. By attaching the connector of thisinvention to such a neutral bar, a circuit breaker of a larger currentrating may be installed in a panelboard and the larger neutral wireassociated therewith may be accommodated by the neutral bar as modifiedby the connector.

The object of the invention is to provide a simple electrical connectorreadily attachable to a neutral bar and operable to secure a larger wirethan can be accommodated by the neutral bar itself.

Other objects of the invention will appear from time to time as thefollowing specification proceeds and with reference to the accompanyingdrawings in which:

FIGURE 1 is an elevational view of a portion of a neutral bar with aconnector constructed in accordance with the invention attached thereto;

FIGURE 2 is a sectional view taken substantially along the line 2-2 ofFIGURE 1;

FIGURE 3 is a sectional view taken substantially along the line 3-3 ofFIGURE 2;

FIGURE 4 is a sectional view taken substantially along the line 4-4 ofFIGURE 3;

FIGURE 5 is a perspective view of the body portion of the connector withthe clamping screw and formed clamping plate therein;

FIGURE 6 is a perspective view of the attaching base member of theconnector;

FIGURE 7 is a view similar to FIGURE 1, but showing a modified form ofconnector constructed in accordance With the invention;

FIGURE 8 is a sectional view taken substantially along the line 88 ofFIGURE 7;

FIGURE 9 is a sectional view taken substantially along the line 99 ofFIGURE 8;

FIGURE 10 is a sectional view taken substantially along the line Ill-10of FIGURE 9;

FIGURE 11 is a perspective view of the body portion of the modifiedconnector with the clamping screw and formed clamping plate therein; and

FIGURE 12 is a perspective view of the attaching base member of themodified connector.

The embodiment of the invention shown in FIGURES 1 through 6 will firstbe described.

The connector is generally indicated by the numeral 10 in FIGURES 1 to 3and is shown mounted on a portion of a neutral bar 12. The neutral bar12 may be formed as claimed in copending application, Serial No.168,733, filed on January 25, 1962, and assigned to the assignee of thepresent application, and is provided with a series of holes 14 extendingtherethrough for receiving the ends of electrical conductors such as aconductor 16. Each hole 14 communicates with a threaded hole 18extending through the top of the neutral bar for receiving a clampingscrew such as a screw 20 adapted to clamp the end of a conductor 16 tothe neutral bar.

A conductor 22 too large to be received by a hole 14 may be connected tothe neutral bar 12 by the use of a connector 10 constructed inaccordance with the invention. The connector 10 includes a generallyU-shaped body portion 24, legs 25 and 26 of which are provided withgenerally rectangular apertures 27 and 28 (FIGURE 5) and base or bightportion 29 of which is centrally provided with a threaded hole forreceiving a clamping screw 30 having a formed clamping plate 31pivotally connected to the lower end thereof. In the embodiment shown,the clamping plate 31 has a pair of opposite extremities 32 and 33projecting into the apertures 27 and 28, respectively, and a second pairof extremities 34 and 35 projecting at right angles to the extremities32 and 33 between the legs 25 and 26. The extremiities 32, 33, 34, and35 are preferably concave-convex with the concave side directed awayfrom the screw 30.

The aperture 27 divides the leg 25 into a pair of side portions 37 and38 connected at their outer ends by a connecting portion 39. Similarly,the aperture 28 divides the leg 26 into a pair of side portions 41 and42 connected at their outer ends by a connecting portion 43.

The connector 10 also includes an attaching base mem ber 45 best shownin FIGURE 6. The base member 45 is generally rectangular in shape but isprovided with a pair of opposite notches 46 and 47 centrally of thelonger sides thereof, a hole 48 adjacent one end thereof, a nub or boss49 adjacent the other end thereof, and a tang 50 centrally of theshorter side thereof adjacent the boss 49. The tang 50 is bent over toproject oppositely from the boss 49.

The attaching base member 45 is assembled in the body portion 24 withthe clamping screw 30 and formed clamping plate 31 in raised position,the member 45 being inserted edgewise between the legs 25 and 26 andthen maneuvered to the fiatwise position of the drawings with the sideportions 38 and 42 of the legs 25 and 26 received in the notches 46 and47, respectively, and with the tang 50 extending away from the clampingscrew 30.

To attach the connector 10 to the neutral bar 12, the screws 20 arefirst removed from three consecutive holes 18. The connector is thenassembled to the bar by placing it over the top of the bar with the legs25 and 26 on opposite sides and inserting the tang 5!} of the attachingbase member 45 in an end one of the three holes. A screw 20 is theninserted through the hole 48 in the member 45 and threaded securely intothe other end hole of the three consecutive holes 18.

The body portion 24 may then be raised to the position shown in FIGURE 1and 2 and an end of the conductor 22 inserted, after which the clampingscrew 30 may be tightened to clamp the conductor 22 against the boss 49as shown in FIGURE 3.

The embodiment of the invention shown in FIGURES 7 through 12 includes aconnector generally indicated by the numeral 10 having a body portion24, a clamping screw 30, and a formed clamping plate 31 identical to thebody portion 24, clamping screw 30, and formed clamping plate 31,respectively, of the embodiment of the invention shown in FIGURES 1through 6 and therefore identically numbered and not herein furtherdescribed.

The connector 10' also includes an attaching base member best shown inFIGURE 12. The base member 55 includes a generally cross-shaped portion56 adapted to fit within the body portion 24, and an extension 57adapted to be secured to the neutral bar 12. The crossshaped portion 56has a nub or boss 58 formed centrally of the top surface thereof,projecting end portions 59 and 60 adapted to extend parallel to andbetween the legs 25 and 26, and projecting side portions 61 and 62adapted to project through the apertures 27 and 28, respectively. Theside portions 61 and 62 are bent downwardly to extend in a directionaway from the boss 58 and are formed with tapered faces 63 and 64 at therespective bends.

The extension 57 forms a continuation of the projecting end portion 60,but it is formed wider than the portion 60 to provide a pair of notches65 and 66 adapted to receive the respective side portions 38 and 42 ofthe legs 25 and 26 as shown in FIGURE 10. The extension 57 is furtherprovided with a hole 69 and an open-ended slot 70.

The attaching base member 55 is assembled in the body portion 24 withthe clamping screw 30 and formed clamping plate 31 in raised position,the member 55 being inserted between the legs 25 and 26 edgewise andthen maneuvered to the fiatwise position of the drawings with the sideportions 38 and 42 of the legs 25 and 26 received in the notches 65 and66, respectively, and the projecting end portions 61 and 62 in theapertures 27 and 28, respectively, the tapered faces 63 and 64 providingsufficient clearance to enable the member 55 to be turned into properposition relative to the body portion 24.

To attach the connector to the neutral bar 12, at least threeconsecutive screws are first removed from their respective holes 18, anda fourth one partially threaded out. The connector is then assembled tothe bar by placing it over the top of the bar with the legs and 26 onopposite sides and inserting the base member 55 under the partiallyremoved fourth screw 20 so that said fourth screw is received in theopen-ended slot 70. The fourth screw is then tightly secured after oneof the other screws is inserted through the hole 69 and tightened to thebar. The downwardly turned outer ends of the projecting end portions 61and 62 aid in maintaining the body portion 24 of the connector 10'assembled to the bar.

It will be seen that a simple electrical connector has been providedwhich is readily attachable to a neutral bar for securing a larger wirethan can be accommodated by the neutral bar itself.

I claim:

1. A neutral bar assembly comprising an elongated neutral bar having aportion generally rectangular in cross section and having a series ofholes of predetermined size extending therethrough from one side toanother and respectively adapted to receive the ends of electricalconductors, said neutral bar also having a corresponding series ofthreaded holes extending through a top surface thereof substantiallyperpendicularly to and respectively communicating with said conductorreceiving holes, said threaded holes being adapted to receive screws forclamping to said neutral bar within said conductor receiving holeselectrical conductors of a size up to the predetermined size of saidconductor receiving holes, and a connector secured to said neutral bar,said connector including a generally U-shaped body having a bightportion and a pair of substantially parallel legs extending from saidbight portion and adapted to straddle said neutral bar, each of saidlegs having a generally rectangular aperture therethrough dividing therespective leg into a pair of substantially parallel side portionsextending from said bight portion and a connecting portion joining theends of said side portions opposite said bight portion, a clamping screwthreadedly mounted in said bight portion, and a generally fiat attachingmember secured to said neutral bar and extending longitudinally thereof,said attaching member having oppositely projecting portions extendingtransversely of said neutral bar respectively into said apertures, saidbody being reciprocably mounted on said transversely extending portions,and said apertures being larger than the predetermined size of saidconductor receiving holes in said neutral bar after allowance is madefor said transversely extending portions of said attaching member.

2. A neutral bar assembly as claimed in claim 1, including a clampingplate pivotally connected to the lower end of the clamping screw mountedin said bight portion, said clamping plate having oppositely projectingportions extending transversely of said neutral bar respectively intosaid apertures.

3. A neutral bar assembly as claimed in claim 1, wherein said attachingmember is formed with a pair of oppositely disposed notches respectivelyadjacent said transversely extending portions thereof, and each of saidlegs of said body has one of its said side portions disposed in arespective one of said notches.

4. A neutral bar assembly as claimed in claim 1, wherein saidtransversely extending portions of said attaching member project throughsaid apertures beyond said legs of said body and are bent toward saidneutral bar.

5. A neutral bar assembly as claimed in claim 1, wherein one end of saidattaching member projects beyond said body longitudinally of saidneutral bar and said projecting one end is provided with a mounting holeextending therethrough and an open-ended slot spaced longitudinally ofsaid mounting hole, and said attaching member is secured to said neutralbar solely by two screws extending respectively through said mountinghole and said open-ended slot and threaded respectively into a pair ofadjacent threaded holes of said neutral bar.

6. A neutral bar assembly as claimed in claim 1, wherein one end of saidattaching member projects beyond said body longitudinally of saidneutral bar and said projecting one end is provided with a mounting holeextending therethrough and the other end of said attaching member isprovided with a bent tang, and said attaching member is secured to saidneutral bar solely by a single screw extending through said mountinghole and threaded into one of said threaded holes of said neutral bar,the said bent tang projecting into a third of said threaded holes ofsaid neutral bar spaced from said one threaded hole by a second of saidthreaded holes.

References Cited in the file of this patent UNITED STATES PATENTS1,943,660 Edwards Jan. 16, 1934 2,476,863 Hawes July 19, 1949 2,539,628Kingdon Jan. 30, 1951 2,748,365 Speck May 29, 1956 FOREIGN PATENTS496,659 Canada Oct. 6, 1953

1. A NEUTRAL BAR ASSEMBLY COMPRISING AN ELONGATED NEUTRAL BAR HAVING APORTION GENERALLY RECTANGULAR IN CROSS SECTION AND HAVING A SERIES OFHOLES OF PREDETERMINED SIZE EXTENDING THERETHROUGH FROM ONE SIDE TOANOTHER AND RESPECTIVELY ADAPTED TO RECEIVE THE ENDS OF ELECTRICALCONDUCTORS, SAID NEUTRAL BAR ALSO HAVING A CORRESPONDING SERIES OFTHREADED HOLES EXTENDING THROUGH A TOP SURFACE THEREOF SUBSTANTIALLYPERPENDICULARLY TO AND RESPECTIVELY COMMUNICATING WITH SAID CONDUCTORRECEIVING HOLES, SAID THREADED HOLES BEING ADAPTED TO RECEIVE SCREWS FORCLAMPING TO SAID NEUTRAL BAR WITHIN SAID CONDUCTOR RECEIVING HOLESELECTRICAL CONDUCTORS OF A SIZE UP TO THE PREDETERMINED SIZE OF SAIDCONDUCTOR RECEIVING HOLES, AND A CONNECTOR SECURED TO SAID NEUTRAL BAR,SAID CONNECTOR INCLUDING A GENERALLY U-SHAPED BODY HAVING A BIGHTPORTION AND A PAIR OF SUBSTANTIALLY PARALLEL LEGS EXTENDING FROM SAIDBIGHT PORTION AND ADAPTED TO STRADDLE SAID NEUTRAL BAR, EACH OF SAIDLEGS HAVING A GENERALLY RECTANGULAR APERTURE THERETHROUGH DIVIDING THERESPECTIVE LEG INTO A PAIR OF SUBSTANTIALLY PARALLEL SIDE PORTIONSEXTENDING FROM SAID BIGHT PORTION AND A CONNECTING PORTION JOINING THEENDS OF SAID SIDE PORTIONS OPPOSITE SAID BIGHT PORTION, A CLAMPING SCREWTHREADEDLY MOUNTED IN SAID BIGHT PORTION, AND A GENERALLY FLAT ATTACHINGMEMBER SECURED TO SAID NEUTRAL BAR AND EXTENDING LONGITUDINALLY THEREOF,SAID ATTACHING MEMBER HAVING OPPOSITELY PROJECTING PORTIONS EXTENDINGTRANSVERSELY OF SAID NEUTRAL BAR RESPECTIVELY INTO SAID APERTURES, SAIDBODY BEING RECIPROCABLY MOUNTED ON SAID TRANSVERSELY EXTENDING PORTIONS,AND SAID APERTURES BEING LARGER THAN THE PREDETERMINED SIZE OF SAIDCONDUCTOR RECEIVING HOLES IN SAID NEUTRAL BAR AFTER ALLOWANCE IS MADEFOR SAID TRANSVERSELY EXTENDING PORTIONS OF SAID ATTACHING MEMBER.